Fire-arch



T. A. MARSH.

FIRE ARCH. APPLlCATLON F ILED OCT. I9, 1918- Patented 0015. is, 1921.

2 SHEET$SHEET 1.

v T. A. MARSH;

FIRE ARCH.

APPLICATION FILED 00119, 1918.

2 SHEETS-SHEET 2- Patented Oct. 18, 1921..

mm QM em t UNITED sraras PATENT OFFICE.

THOMAS A. MARSH, OF CHICAGO, ILLINOIS, ASSIGNOR, T0 GREEN ENGINEERING COM- PANY, OF EAST CHICAGO, INDIANA, A CORPORATION OF ILLINOIS.

FIRE-ARGE- Application filed. October 19, .1918.

Among the objects ofqmy invention is to. so construct a fire-arch that .the under or,

heat radiating surface thereof is prevented from having its temperature reduced by the currents of cold air drawn into the combustion chamber with the incoming fresh or green fuel as it is fed into the combustion chamber beneath the fire-arch.

The invention consists further in the matters hereinafter described and more particularly pointed out in the appended claims.

In the accompanying drawings: Figure 1 is a longitudinal sectional vlew of a furnace of the chain grate type, the

fire-arch of which embodies the features of my invention, the fuel hopper being shown in elevation;

Fig. 2 is an enlarged longitudinal sectional view with parts in elevation of the fire-arch shown in Fig. 1, the plastic material used about the adapter plates being omitted for the purposes of illustration;

Fig. 3 is a fragmentary transverse vertical sectional view taken on line 3-3 of Fig. 2, the plastic material being omitted for the same purpose;

Fig. 4 is a fragmentary transverse vertical sectional view taken on line 4-4: of Fig. 2;

Fig. 5 is a perspective view of the adapter member, to be hereinafter described in detail; and

Fig. 6 is a longitudinal sectional view of the fire-arch embodying another form of my invention.

In the furnace structure shown in the drawings there is a combustion chamber or Specification of Letters Patent.

Patented Oct. 18, 1921.

Serial No. 258,845.

the front of the furnace discharges into the fire box on the grate below a fire arch 15 embodying the. features of my invention.

In furnaces ofthis general type, the upper surface of the fuel layer adjacent its entrance into the fire box is ignited by the heat radiated downward thereagainst from the fire-arch. To gain an efficient ignition of the fuel layer as it is progressed beneath the fire-arch, cooling or reducing the temperature of the radiating or under surface of the fire-arch must be guarded against as much as possible, otherwise the heat radiated from suchsurface will vary and an inefiicient ignition will be produced. As the fresh or green fuel is fed into the fire boxfrom the hopper, drafts of cold air are drawn into the combustion chamber and tend to travel along the under or radiating surface of the fire-arch and reduce the temperature thereof.

It is among the objects of my. invention to overcome this difiiculty, and I do so by providing the fire-arch with one or more steps in its under surface to divert the drafts of cold air away from the under surface of the fire-arch and thus avoid coolin the same. By my invention an efieotive ignition of the upper surface of the fuel layer is gained as it is carried beneath the fire-arch.

One form of fire-arch of my invention is shown in Figs. 1 to 5, and as shown said arch extends across the fire box 10 between the side walls thereof, and has an under or heat radiating surface 16. The arch is formed of a plurality of blocks 17, 17, arranged in rows extending inward from the inner wall 14 of the fuel hopper. The blocks in each row abut and have their side faces against the opposed side faces of the blocks in the adjacent rows, as shown in Fig. 4. Said blocks are suspended from I-beams 18, 18, which extend inward from the fuel hopper and have base flanges 19, as shown in Fi s. 2 and 4. In the side face of each block 1 is a groove or channel 20 to receive the base flange 19 of the associated I-beam for supporting the block. There is an I-beam 18 .between each two rows of blocks 17, and the grooves 20 in the opposed side faces of the blocks register to receive the base flanges 19 of the I-bcam therebetween. The top of each block is curved, as

shown, to clear the I-beam and permit the blocks to be readily slid onto the base flanges 19.

The I-beams18 are supported from channel irons 21, 21 extending transversely across the top of the fire-arch between the side walls of the furnace setting. One channel iron 21 is adjacent the fuel hopper 14, and the other adjacent the inner end of the arch. Said members 21 are spaced apart by bars 22.

For suspending the I-beams 18 from said channel irons 21, hook-shaped members 23, 23 are provided; two for each I-beam and one engaged with the base flange 24 of one channel iron, and the other with the base flange 24 of the other channel iron, as shown in Fig. 2. Each hook member 23 is provided with a slide-way 25 to receive the upper enlarged edge 26 of the associated I-beam 18, a set screw 27 being used to clamp the parts together.

To make the radiating or under surface 16 of the fire-arch 15 step-shaped, as shown in Fig. 1, I provide at the hopper 14 blocks 28, which extend below the blocks 17; There is a block 28 at the end of each row of blocks 17, and the blocks 28 bear against the hopper wall14 and form a step extending across the fire-arch from one side wall of the furnace setting to the other. In building the fire-arch, it is preferable that the blocks 28 be placed in position first, and then the blocks 17, 17 applied afterward. To suspend the blocks 28 from the I-beams 18, I provide adapter plates 29, which, as shown, have the general form of I-beams, with a base flange or web 30 and a head ortion 31 provided with an upwardly opening channel 32 having overhanging flanges 33, the inner or opposed edges of which are spaced apart to allow the vertical or upright web of the I-beam 18 to extend upwardly therebetween. Said channel 32 is open at its ends to allow the adapter 29 to be slid on the base flange of the I-beam 18 and be clamped thereto by a set screw 34. The opposed side faces of the blocks 28 contact and in each is provided a channel or groove 35 to receive the base flange 30 of the associated adapter 29, there being an adapter 29 between each two opposed blocks 28, as shown. The adapter plates 29 suspend the blocks 28 below the blocks 17 to provide the step in the fire-arch at the place where the cold air enters the fire box with the incoming fresh or green fuel, and thus the blocks 28 serve to direct such cold air away from the heat-radiating or under surface 16 of said arch for the purpose heretofore stated.

The I-beams 18 are inclined upward, as shown, and so are the blocks 17. The tops of the blocks 28 are curved but not inclined as the I-beams, so the adapter plates 29 have their flanges 3O horizontal and their upper flanges 31 inclined corresponding to the inclination of the I-beams 18, thus making the vertical web of each plate higher at one end than at the other so as to properly support the blocks 28 in the positions required. (See Figs. 2 and 5.) The space between the tops of the blocks 28 and the I-beams is filled with plastic material 36, which when set tends to bind the several blocks together.

In Fig. l, the currents of cold air drawn into the combustion chamber through the fuel hopper are indicated by arrows, marked a, while the arrows marked 5 indicate the heat waves radiated from the under surface of the fire-arch, thus indicating the manner in which the step in the arch serves'the purpose of my invention.

Instead of one step, two may be used, as shown in Fig. 6, wherein I employ another set of blocks 37 in advance of the ones 28. Said blocks 37 extend downward below the blocks 17 but not below the blocks 28. The blocks 37 are suspended from the I-beams 18 by adapter plates made for that purpose and like the ones previously described only not as high.

The fire-arch 15 is covered by an archcover 38 made of connected metal plates, with one extending outward from the bottom of the boiler door 39, behind which is one of the headers 40 of the boiler. Said header 40 rests on or is supported above the curtain wall 41, which extends upward from the inner end of the fire-arch. The boiler is' provided with another header 42, which rests on or is supported above the rear wall 43 of the furnace setting, and between the headers extend water tubes 44.

While I have shown and described herein in detail a structure embodying the features of my invention, yet it is to be of course understood that the, various details of construction and arrangement of parts shown may be variously changed and modified without departing from the spirit and scope of my invention, and I do not wish to be restricted to the exact details of construction and arrangement of parts illustrated, except as pointed out in the appended claims.

I claim as my invention:

1. A fire-arch, comprising a plurality of laterally spaced beams extending from front to rear of said arch, a row of blocks for each of the spaces between said beams, a plurality of the blocks in each row engaged with the beams at opposite sides thereof and suspended from said beams with the lower faces of the blocks in the same plane, the front block in each row extending below the remaining blocks in the row to provide a step at the front end of the row, said front blocks having their upper ends terminating short of the beams thereabove, and means for suspending said front blocks from said beams.

2. A fire-arch, comprising a plurality of laterally spaced beams extending from front to rear of said arch, a row of blocks for each of the spaces between said beams, a plurality of the blocks in each row engaged with the beams at opposite sides thereof and suspended from said beams with the lower faces of the blocks in the same plane, the front block in each row extending below the remaining blocks in the row to provide a step at the front end of the row, and adapter plates connected with and depending from said beams at the front blocks, the latter having their upper ends terminating short of the beams and extending into the spaces between said plates and engaging the same at opposite sides thereof.

3. A fire-arch, comprising a plurality of laterally spaced I-beams extending from front to rear of said arch, a row of blocks for each of the spaces between said beams, a plurality of the blocks in each row engaged with the base flanges of said beams at opposite sides thereof and suspended from said beams with the lower faces of the blocks in the same plane, the front block in each row extending below the remaining blocks in the row to provide a step at the front end of the row, and adapter plates for suspending the front blocks from said beams, said plates having flanges at their upper ends to engage over the base flanges of the I-beams and flanges at their lower ends to engage in the sides of the front blocks therebetween.

4. A fire-arch, comprising a plurality of laterally spaced I-beams extending from front to rear of said arch, a row of blocks I for each of the spaces between said beams, a plurality of the blocks in each row engaged with the base flanges of said beams at opposite sides thereof and suspended from said beams with the lower faces of the blocks in the same plane, the front block in each row extending below the remaining'blocks in the row to provide a step at the front end of the row, and adapter plates for suspending the front blocks from said beams, said plates being provided at their upper ends with channels to receive the base flanges of said I-beams and with flanges at their lower ends to engage in the sides of the front blocks therebetween.

5. An adapter plate of the character described, comprising a web having a base flange extending along one of the longitudinal edges of the web and projecting laterally therefrom on opposite sides of the same, said web having its other longitudinal edge inclined upwardly from one end of the web to the other and provided withflanges forming a channel open at its ends, said flanges terminating short of each other to provide a slot opening into the channel lengthwise thereof.

In testimony that I claim the foregoing as my invention, 1 affix my signature in the presence of two witnesses, this 15th day of October, A. D. 1918.

THOMAS A. MARSH.

Witnesses: I

EUGENE H. BULL, A. P. STRONG. 

